CN106543000A - A kind of esterification purifying and cleaning production technology - Google Patents
A kind of esterification purifying and cleaning production technology Download PDFInfo
- Publication number
- CN106543000A CN106543000A CN201610952303.2A CN201610952303A CN106543000A CN 106543000 A CN106543000 A CN 106543000A CN 201610952303 A CN201610952303 A CN 201610952303A CN 106543000 A CN106543000 A CN 106543000A
- Authority
- CN
- China
- Prior art keywords
- catalyst
- water
- capryl alcohol
- ester
- esterification
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/48—Separation; Purification; Stabilisation; Use of additives
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/48—Separation; Purification; Stabilisation; Use of additives
- C07C67/56—Separation; Purification; Stabilisation; Use of additives by solid-liquid treatment; by chemisorption
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The present invention relates to a kind of esterification purifying and cleaning production technology.The present invention adopts nano solid acid catalyst catalytic esterification to improve reactivity, and carries out follow-up subtractive process using membrane separation technique, including neutralization washing, catalyst separate and reduce pressure dealcoholysis.The process for refining realizes the serialization of whole technical process, automation mechanized operation, and production efficiency is high, and product quality is stable.The separation process of catalyst and esterification reaction process are coupled in same system, fine suspended state catalyst are solved and serious problems is lost in during separating and recovering.Membrance separation energy consumption is low, and the organic efficiency of capryl alcohol is high.
Description
Technical field
The present invention relates to a kind of esterification refines continuous production technology, membrance separation in more particularly to a kind of esterification reaction process
The production technology of catalyst is reclaimed in refined dealcoholysis.
Background technology
Dioctyl phthalate plasticizer has that the nonpoisonous and tasteless, compatibility is good, plasticizing efficiency is high, be easily biodegradable and
The advantages of volatility is little, tolerance to cold, light resistance and has excellent water-resistance, be widely used in food and medical instrumentation package, cosmetics,
The fields such as article of everyday use, toy, personal hygiene article.
Traditional production technology is usually the lactate synthesis in the presence of phthalandione ester catalyst by phthalic anhydride and capryl alcohol, reacts and produces
The post processing of thing will be through distillation dealcoholysis, in alkali and washing, stripping, decolourize to finally obtain finished product.
Using conventionally produced, although product quality is more stable, can be up to state standards, but this production
Method there is also obvious defect, such as：
Although 1. phthalate ester catalyst activity is high, there are many shortcomings in it：Long the production cycle, conversion ratio are low, by-product
Many, this refined and recovery to product brings difficulty.
2. the post processing of traditional handicraft mainly include distillation dealcoholysis, in alkali and washing, stripping, the step such as decolourize, between belonging to
Have a rest operation, process is discontinuous, and labor intensity is larger；Alkali neutralization, washing, and catalyst is removed, cause complex process, produce useless
The water yield is big, and low separation efficiency causes product to be lost in；Vacuum distillation dealcoholysis observable index is higher, will can be only achieved through multistage dealcoholysis
Require, complex operation, low separation efficiency, long flow path, produce the three wastes more；Device input is big, and production scale is little, reduces production
Efficiency.
Liquid acid is replaced using solid acid catalyst, liquid acid pollution of ecological environment in esterification technique, corruption can be solved
Erosion equipment and harm production operation safety problem.Generally, catalyst granules is thinner, and reaction rate is faster, but granule
The separation of degree catalyst is more difficult.The separation methods such as traditional gravitational settling, centrifugation, flotation, cake filtration, in-depth filtration
Effectively which can not be kept completely separate out from liquid-phase product, cause catalyst loss serious, and product can be affected
Purity.
In addition, restriction and environmental protection requirement more and more higher of the country for plasticizer, for this purpose, in the urgent need to production
Traditional handicraft is reformed, and works out a kind of production technology of new, rational, advanced, environmental protection as early as possible, to meet market need
Ask.
The content of the invention
It is an object of the invention to provide the production work of catalyst is reclaimed in the refined dealcoholysis of membrance separation in a kind of esterification reaction process
Skill, successfully can realize product purification using inorganic membrane separation technique using the technique, can effectively solve subparticle
The separation of solid catalyst, can improve dealcoholysis and dewatering efficiency；Product purity can also be improved simultaneously, and reducing energy consumption reduces useless
Water discharge capacity, continuous automatic production improve efficiency, increase production scale.
The technical scheme is that：
A kind of esterification purifying and cleaning production technology, including step：
（1）The esterification of phthalic anhydride and capryl alcohol：Phthalic anhydride, capryl alcohol and solid acid catalyst are added in reactor, in the anti-of routine
Answer；
（2）In embrane method and wash：After esterification terminates, in addition aqueous slkali with after, standing makes ester water stratification, takes upper strata ester
Layer continuously adds water together into hydrophilic porous membrane module, carries out aqueous phase separation, until ester layer is washed till neutrality, obtains retaining side
Concentration material, mainly including capryl alcohol, o-phthalic acid dibutyl ester and catalyst；Per-meate side is separated and discharges water to wastewater treatment；Institute
It is ceramic membrane to state hydrophilic porous membrane module, and average pore size is 50～400 nm, 0.1～0.5 MPa of operating pressure；
（3）Catalyst is separated：The concentration material of retention side carries out solid-liquid separation into lipophile porous-membrane module, wherein capryl alcohol and
O-phthalic acid dibutyl ester Jing per-meate sides are separated, and the solid catalyst of retention is reclaimed；The lipophile porous-membrane module is
Modified ceramic film, average pore size are 50～400 nm, and the modified employing organo silane coupling agent of ceramic membrane used is to ceramic membrane
Chemical modification is carried out, contact angle of the water droplet on film surface is 90～170 degree；0.1～0.6 MPa of operating pressure；
（4）Infiltration evaporation dealcoholysis：The mixture of capryl alcohol and o-phthalic acid dibutyl ester is delivered into into infiltration vaporization membrane module, it is pungent
Alcohol is isolated from per-meate side and is reclaimed, and obtains the o-phthalic acid dibutyl ester for concentrating；The supporting layer of the infiltrating and vaporizing membrane is oxygen
Change aluminum, stratum disjunctum is polydimethylsiloxane；
（5）Embrane method wastewater treatment：Step（2）In waste water using activated carbon filtration after, into reverse osmosis membrane processing, operating pressure
0.1～0.5 MPa, the water purification for obtaining return neutralization water-washing step reuse.
Solid acid described in above-mentioned technique is molecular sieve catalyst, super acidic catalyst or heteropolyacid catalyst；Catalysis
The particle diameter of agent is 10～100 nm.
Step described in above-mentioned technique（1）In, the mol ratio of phthalic anhydride and capryl alcohol is 1:2.6～1:4；Described solid catalyst
Total raw material mass percent is accounted for for 1%～3%；Described enzymatic synthesis condition is：React 2～4 hours at 200～240 DEG C.
Step described in above-mentioned technique（2）In, the aqueous slkali is sodium carbonate, sodium hydroxide or hydrogen-oxygen that concentration is 3%～5%
Change potassium solution.
The beneficial effect of the invention is：
1. present invention achieves the continuous operation of whole technical process, high degree of automation, labor intensity are little, easy to operate,
Production efficiency is high.
2., using in embrane method and washing process, separation efficiency is high, can be run with serialization, compared with traditional handicraft waste water for the present invention
Discharge capacity is little, and environmental pollution is little；And reverse-osmosis treated is carried out to waste water, directly obtain water purification reuse.
3. the present invention removes alcohol using infiltration evaporation, and energy consumption is low, pollution-free, meets environmental requirement, and separation efficiency is high, operation
It is continuous simple, and realize " reclaim-recycle " continuous process of capryl alcohol.
4. present invention achieves continuous operation, solves the separation problem of fine suspended state catalyst in esterification,
" reaction-separation-reuse " of catalyst can be carried out continuously；Concise in technology, equipment investment are few, reduce the stream of catalyst
Lose, production can be carried out continuously, improve production efficiency.
Specific embodiment
Embodiments of the present invention are illustrated below in conjunction with the accompanying drawings.The following example is merely to illustrate the present invention, but and without
To limit the practical range of the present invention.
Embodiment 1
By phthalic anhydride and capryl alcohol according to 1:In 2.6 mol ratio input reactor, 1% is added（Account for the mass percent of total raw material）'s
50 nm of solid super acid catalyst, closes dog-house, opens chuck heating steam valve, 0.6 MPa of control steam ＜（Gauge pressure）.
Note water outlet situation, pressure in strict control kettle（Gauge pressure）0.05 MPa of ＜, in order to avoid causing slug, reaction maximum temperature control is little
In 200 DEG C, react up to 2 hours, you can sample examination, then sample once per half an hour, when the acid number of thick ester liquid is less than
0.02 mg KOH/g, you can think that esterification terminates, close chuck heating steam valve, close reflux inlet, stop stirring.Open reaction
Kettle condenser is cooled down.
After completion of the reaction, the reaction product material pump for being mixed with catalyst is exported, material enters neutralizing tank after metering, is used
3% Na2CO3Aqueous slkali is neutralized, and then standing makes ester water stratification, water that neutralization water is put in the bottom of neutralizing tank, after metering
In collecting tank.Ester layer is exported by pump, and is washed while continuously adding water, and together into hydrophilic porous ceramic film component, enters water-filling phase
Separate, be washed till neutrality.The concentration material of retention side mainly includes capryl alcohol, DOP and catalyst, adjusts pressure into intermediate storage tank 1,
Per-meate side separates water outlet into wastewater collection tank.Aperture is adopted for 0.03 μm of tubular ceramic membrane, 19 passages, channel internal diameter 4
Mm, cross-flow velocity 1m/s, 0.4 MPa of operating pressure, membrane permeation flux 0.5m3·m-2·h-1。
Material in intermediate storage tank 1 enters organophilic porous ceramicss membrane module, wherein capryl alcohol, O-phthalic via pump
Dioctyl phthalate Jing per-meate sides are separated into intermediate storage tank 2.Catalyst is trapped, when being concentrated to solid content and reaching 15%, point
Complete from process, returning esterifying kettle is used for lower secondary response.Aperture is adopted for 0.02 μm of ceramic membrane, 7 passages, and ceramics used
The modified employing organo silane coupling agent of film carries out chemical modification to ceramic membrane, and contact angle of the water droplet on film surface is 90～170
Degree；Channel internal diameter 6mm, cross-flow velocity 1m/s, operating pressure 0.3MPa, membrane permeation flux 0.1m3·m-2·h-1。
Material in intermediate storage tank 2 with being pumped into into infiltration vaporization membrane module, preferentially separate by capryl alcohol, returns ester
Change kettle and continue cycling through utilization, the dioctyl phthalate of concentration is packaged to be finished product through decolouring, filter pressing.Phthalic acid two
The yield of monooctyl ester is 98%.Using polydimethylsiloxane（PDMS）/ aluminium oxide infiltrating and vaporizing membrane, 0.2 MPa of operating pressure, film
Permeation flux 4kgm-2·h-1。
After the waste water that neutralization washing is produced is using activated carbon filtration, into reverse osmosis membrane processing, 0.1 MPa of operating pressure,
The water purification for obtaining returns neutralization water-washing step reuse.
Embodiment 2
By phthalic anhydride and capryl alcohol according to 1:In 3 mol ratio input reactor, 2% is added（Account for the mass percent of total raw material）Point
10 nm of sub- sieve catalyst, closes dog-house, opens chuck heating steam valve, 0.6 MPa of control steam ＜（Gauge pressure）.Note
Regimen condition, pressure in strict control kettle（Gauge pressure）0.05 MPa of ＜, in order to avoid causing slug, reaction maximum temperature control is less than 220
DEG C, reacting up to 3 hours, sample examination is then sampled once per half an hour, when the acid number of thick ester liquid is less than 0.02mgKOH/
G, you can think that esterification terminates, closes chuck heating steam valve, closes reflux inlet, stop stirring.Open the cooling of reactor condenser.
After completion of the reaction, the reaction product material pump for being mixed with catalyst is exported, material enters neutralizing tank after metering, is used
5% NaOH aqueous slkalis neutralization, then standing makes ester water stratification, and water is put into neutralization water and is received in the bottom of neutralizing tank, after metering
In collection tank.Ester layer is exported by pump, and is washed while continuously adding water, and together into hydrophilic porous ceramic film component, enters water-filling phase point
From being washed till neutrality.The concentration material of retention side mainly includes capryl alcohol, dioctyl phthalate and catalyst, into middle storage
Tank 1 adjusts pressure, and per-meate side separates water outlet into wastewater collection tank.Aperture is adopted for 0.05 μm of tube type metal film, 19 lead to
Road, channel internal diameter 4mm, cross-flow velocity 5m/s, operating pressure 0.1MPa, membrane permeation flux 0.05m3·m-2·h-1。
Material in intermediate storage tank 1 enters organophilic porous ceramicss membrane module, wherein capryl alcohol, O-phthalic via pump
Dioctyl phthalate Jing per-meate sides are separated into intermediate storage tank 2.Catalyst is trapped, when being concentrated to solid content and reaching 15%, point
Complete from process, returning esterifying kettle is used for lower secondary response.Aperture is adopted for 0.4 μm of ceramic membrane, 7 passages, and ceramic membrane used
Modified employing organo silane coupling agent carry out chemical modification to ceramic membrane, contact angle of the water droplet on film surface is 90～170 degree；
Channel internal diameter 6mm, 7 m/s of cross-flow velocity, operating pressure 0.6MPa, membrane permeation flux 0.8m3·m-2·h-1。
Material in intermediate storage tank 2 with being pumped into into infiltration vaporization membrane module, preferentially separate by capryl alcohol, returns esterification
Kettle continues cycling through utilization, and the dioctyl phthalate of concentration is packaged to be finished product through decolouring, filter pressing.Phthalic acid two is pungent
The yield of ester is 97.0%.Using polydimethylsiloxane（PDMS）/ aluminium oxide infiltrating and vaporizing membrane, 0.2 MPa of operating pressure, film
Permeation flux 4kgm-2·h-1。
After the waste water that neutralization washing is produced is using activated carbon filtration, into reverse osmosis membrane processing, operating pressure 0.3MPa, obtain
The water purification for arriving returns neutralization water-washing step reuse.
Embodiment 3
By phthalic anhydride and capryl alcohol according to 1:In 4 mol ratio input reactor, 3% is added（Account for the mass percent of total raw material）It is miscellaneous
100 nm of many acid catalysts, closes dog-house, opens chuck heating steam valve, 0.6 MPa of control steam ＜（Gauge pressure）.Note
Regimen condition, pressure in strict control kettle（Gauge pressure）0.05 MPa of ＜, in order to avoid causing slug, reaction maximum temperature control is less than 240
DEG C, reacting up to 4 hours, sample examination is then sampled once per half an hour, when the acid number of thick ester liquid is less than 0.02mgKOH/
G, you can think that esterification terminates, closes chuck heating steam valve, closes reflux inlet, stop stirring.Open the cooling of reactor condenser.
After completion of the reaction, the reaction product material pump for being mixed with catalyst is exported, material enters neutralizing tank after metering, is used
4% KOH aqueous slkalis neutralization, then standing makes ester water stratification, and water is put into neutralization water and is received in the bottom of neutralizing tank, after metering
In collection tank.Ester layer is exported by pump, and is washed while continuously adding water, and together into hydrophilic porous ceramic film component, enters water-filling phase point
From being washed till neutrality.The concentration material of retention side mainly includes capryl alcohol, dioctyl phthalate and catalyst, into middle storage
Tank 1 adjusts pressure, and per-meate side separates water outlet into wastewater collection tank.Aperture is adopted for 0.4 μm of ceramic-metal composite film,
19 passages, channel internal diameter 4mm, cross-flow velocity 3m/s, operating pressure 0.5MPa, membrane permeation flux 0.5m3·m-2·h-1。
Material in intermediate storage tank 1 enters organophilic porous ceramicss membrane module, wherein capryl alcohol, O-phthalic via pump
Dioctyl phthalate Jing per-meate sides are separated into intermediate storage tank 2.Catalyst is trapped, when being concentrated to solid content and reaching 15%,
Separation process is completed, and returning esterifying kettle is used for lower secondary response.Aperture is adopted for 0.05 μm of ceramic membrane, 7 passages, and pottery used
The modified employing organo silane coupling agent of porcelain film carries out chemical modification to ceramic membrane, and contact angle of the water droplet on film surface be 90～
170 degree；Channel internal diameter 6mm, 2 m/s of cross-flow velocity, operating pressure 0.1MPa, 0.02 m of membrane permeation flux3·m-2·h-1。
Material in intermediate storage tank 2 with being pumped into into infiltration vaporization membrane module, preferentially separate by capryl alcohol, returns esterification
Kettle continues cycling through utilization, and the dioctyl phthalate of concentration is packaged to be finished product through decolouring, filter pressing.Phthalic acid two is pungent
The yield of ester is 96.4%.Using polydimethylsiloxane（PDMS）/ aluminium oxide infiltrating and vaporizing membrane, 0.2 MPa of operating pressure, film
Permeation flux 4kgm-2·h-1。
After the waste water that neutralization washing is produced is using activated carbon filtration, into reverse osmosis membrane processing, 0.5 MPa of operating pressure, obtain
Water purification return neutralization water-washing step reuse.
Claims (4)
1. it is a kind of to be esterified purifying and cleaning production technology, it is characterised in that including step：
（1）The esterification of phthalic anhydride and capryl alcohol：Phthalic anhydride, capryl alcohol and solid acid catalyst are added to carry out being esterified instead in reactor
Should；
（2）In embrane method and wash：After esterification terminates, in addition aqueous slkali with after, standing makes ester water stratification, takes upper strata ester
Layer continuously adds water together into hydrophilic porous membrane module, carries out aqueous phase separation, until ester layer is washed till neutrality, obtains retaining side
Concentration material, mainly including capryl alcohol, o-phthalic acid dibutyl ester and catalyst；Per-meate side is separated and discharges water to wastewater treatment；Institute
It is ceramic membrane to state hydrophilic porous membrane module, and average pore size is 50～400 nm, 0.1～0.5 MPa of operating pressure；
（3）Catalyst is separated：The concentration material of retention side carries out solid-liquid separation into lipophile porous-membrane module, wherein capryl alcohol and
O-phthalic acid dibutyl ester Jing per-meate sides are separated, and the solid catalyst of retention is reclaimed；The lipophile porous-membrane module is
Modified ceramic film, average pore size are 50～400 nm, and the modified employing organo silane coupling agent of ceramic membrane used is to ceramic membrane
Chemical modification is carried out, contact angle of the water droplet on film surface is 90～170 degree；0.1～0.6 MPa of operating pressure；
（4）Infiltration evaporation dealcoholysis：The mixture of capryl alcohol and o-phthalic acid dibutyl ester is delivered into into infiltration vaporization membrane module, it is pungent
Alcohol is isolated from per-meate side and is reclaimed, and obtains the o-phthalic acid dibutyl ester for concentrating；The supporting layer of the infiltrating and vaporizing membrane is oxygen
Change aluminum, stratum disjunctum is polydimethylsiloxane；
（5）Embrane method wastewater treatment：Step（2）In waste water using activated carbon filtration after, into reverse osmosis membrane processing, operating pressure
0.1～0.5 MPa, the water purification for obtaining return neutralization water-washing step reuse.
2. one kind according to claim 1 is esterified purifying and cleaning production technology, it is characterised in that：Described solid acid is point
Sub- sieve catalyst, super acidic catalyst or heteropolyacid catalyst；The particle diameter of catalyst is 10～100 nm.
3. one kind according to claim 1 is esterified purifying and cleaning production technology, it is characterised in that：Step（1）In, phthalic anhydride and
The mol ratio of capryl alcohol is 1:2.6～1:4；Described solid catalyst accounts for total raw material mass percent for 1%～3%；Described ester
Change condition is：React 2～4 hours at 200～240 DEG C.
4. one kind according to claim 1 is esterified purifying and cleaning production technology, it is characterised in that：Step（2）In, the alkali
Solution is sodium carbonate, sodium hydroxide or potassium hydroxide solution that concentration is 3%～5%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610952303.2A CN106543000A (en) | 2016-10-27 | 2016-10-27 | A kind of esterification purifying and cleaning production technology |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610952303.2A CN106543000A (en) | 2016-10-27 | 2016-10-27 | A kind of esterification purifying and cleaning production technology |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN106543000A true CN106543000A (en) | 2017-03-29 |
Family
ID=58392875
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610952303.2A Pending CN106543000A (en) | 2016-10-27 | 2016-10-27 | A kind of esterification purifying and cleaning production technology |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106543000A (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102249916A (en) * | 2011-05-26 | 2011-11-23 | 南京化工职业技术学院 | Continuous production process for tributyl citrate |
| CN105308017A (en) * | 2013-06-07 | 2016-02-03 | 沙特基础工业公司 | Method for purifying dioctyl phthalate |
-
2016
- 2016-10-27 CN CN201610952303.2A patent/CN106543000A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102249916A (en) * | 2011-05-26 | 2011-11-23 | 南京化工职业技术学院 | Continuous production process for tributyl citrate |
| CN105308017A (en) * | 2013-06-07 | 2016-02-03 | 沙特基础工业公司 | Method for purifying dioctyl phthalate |
Non-Patent Citations (1)
| Title |
|---|
| 李冬燕等: "无机分离膜在应用过程中的污染清洁方法", 《江苏化工》 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102249916B (en) | Continuous production process for tributyl citrate | |
| CN108821313B (en) | Method for preparing lithium hydroxide monohydrate by using lithium carbonate | |
| CN102703535A (en) | New technology for producing acrylamide by using ceramic membrane bioreactor | |
| CN103041705B (en) | Device and method for coupling catalyst recovery process with dynamic disc membrane separation process | |
| CN101265179A (en) | Technique for purifying lactate | |
| CN112593094A (en) | Process and device for extracting lithium from salt lake | |
| CN102040476A (en) | Method for separating and purifying 1,3-propylene glycol from fermentation liquor | |
| CN1872729A (en) | Treatment process for recovering industrial wastewater from producing furfural | |
| CN102382203B (en) | High-efficiency extraction process for polysaccharide of lotus seeds | |
| CN107867996B (en) | Method for separating levulinic acid compounds | |
| CN101586129A (en) | Method of preparing sodium gluconate from xylose crystallization mother liquor | |
| CN110743372A (en) | Device and process for preparing methanol and butyl acetate | |
| CN1328244C (en) | Process for producing para-amino-phenol | |
| CN108440281B (en) | Chemical reaction device and application thereof | |
| CN108640844A (en) | The method that triethylamine is recycled from industrial wastewater | |
| CN107987037A (en) | A kind of method that blocking prepares propylene oxide | |
| CN102796011A (en) | Preparation method for p-aminodiphenylamine | |
| CN103241747B (en) | Method for purifying KI in perfluoroalkylethyl acrylate synthesized by-product | |
| CN103059159B (en) | Process for extracting mannan from beer yeast powder | |
| CN105084324A (en) | Impurity removal cleaning method for sodium sulfide | |
| CN106543000A (en) | A kind of esterification purifying and cleaning production technology | |
| CN111825113A (en) | Method for recovering aluminum oxide and sodium oxide from Bayer process red mud | |
| CN106316753A (en) | Separation and purification technology of 2-methylnaphthalene | |
| CN105177072A (en) | Method for producing high-purity sulforaphene from radish seed meal | |
| CN104130096A (en) | Method for continuously separating high-purity longifolene from heavy turpentine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20170329 |